Theoretical study on the interaction between SF6 and TiO2(001) surface: A DFT+U study

Abstract

The research on SF6 degradation and conversion is of great significance for environmental protection. Based on the density functional theory, the adsorption process of SF6 on the TiO2(001) and TiO2(101) surfaces was investigated. The results indicate a strong interaction between SF6 and the TiO2 surface. Significant structural changes in the SF6, such as elongation of the S-F bonds, were observed after adsorption, rendering the SF6 more prone to decomposition. According to Mulliken charge analysis, electron transfer occurs from the TiO2 surface to the SF6, revealing SF6 as an electron acceptor while TiO2 acts as an electron donor. Analysis of the density of states confirms a pronounced electronic orbital overlap between the S/F atoms of SF6 and the Ti/O atoms of TiO2, and the charge density distribution along the Z-axis further supports this charge transfer process. Additionally, experimental studies have demonstrated that TiO2 photocatalysis can accelerate the degradation of SF6 during DBD. This study demonstrates the catalytic potential of TiO2 in the degradation of SF6 insulating gas and provides theoretical support for the efficient and harmless treatment of SF6.